Cheechako, no one is arguing with your suggestion that bridgedeck clearance is an important feature - it is with your suggestion that Lagoons, Privilege
, Catanas and the South African cats
you have seen all feature good clearance, whereas the Gemini's and Catalacs do not.
Firstly, as regards Lagoon
, many of their newer designs are decidedly low on clearance, especially for boats that carry so much beam. Further, despite the claims of Lagoon, most naval architects do not believe that 'nacelles' only inches off the water
are a substitue for proper clearance. Indeed, although it is not named, a photo
of a recent Lagoon is actually used in a recent book on Multihulls to exemplify inadequate clearance.
Furthermore, the newer Catanas feature large, flat bottomed protrusions on the inside of the hulls below the bridgedeck that limit clearance at that location to about a foot. Hence, while the advertised bridgedeck clearance appears fine, the actual clearance is substantially less.
Finally, many of the South African built cats (eg. Leopards and Moorings) were notorious for inadequate bridgedeck clearance when measured by any recognized formula.
Were you aware that what is adequate in terms of bridgedeck clearance is not a static measurement, but one that is most commonly put as a proportion of beam? I gather not. Nevertheless, a much narrower boat such as the Gemini
or Catalac 8M needs much less clearance than a much beamier boat such as your Lagoon. Indeed, I would guess that 15 inches on Rick's cat would be just as effective as 24 inches on your Lagoon.
Furthermore, your posting
completely disregards the effect on pounding of other factors such as:
1. length of the bridgedeck.
2. weight in the ends of the boat.
3. bouyancy in the bows.
4. hydrodynamic aids against compressing the bows such as 'knuckles' above the waterline, but below the bridgedeck.
5. shape of the bridgedeck and especially, whether the leading edge is blunt (frequently due to forward athwartship doubles), or a gentle curve aft (such as Rick's Catalac.
I suspect that Rick's issue with your posting was that it tended to mis-inform a prospective buyer, rather than elucidating her on what is a complex subject.